A variety of different sole constructions are used by the footwear industry. For the most part, each sole construction has characteristics that make it particularly well-suited for specific applications. For example, some constructions are selected for their durability, others for their comfort, while still others are selected for their aesthetic appeal.
Some of the shoes based on comfort typically have enhanced cushioning, which may result in a softer feel to a user's foot. Moreover, cushioning may be used or enhanced in any area of the shoe. Generally, the more cushioning, the softer the shoe feels to the user, resulting in improved comfort.
However, increasing the amount of cushioning, particularly along the entire length of the shoe, often leads to a decrease in breathability and increase in moisture being trapped within the cushioning. The lack of breathability and/or increase in moisture is believed to result in an environment favorable to fungi growth or odor, either of which undesirably counters the beneficial effects of having improved cushioning.
One manner of improving comfort while reducing the disadvantages is to enhance the cushioning in selected areas of the shoe, such as the heel or ball areas.
U.S. Pat. No. 6,474,003 (“Erickson”) appears to relate to a shoe having a recess extending through the insole and an insole pad having a protrusion that protrudes downwardly into the recess. In addition, the insole pad appears to include an aperture for placing the protrusion.
U.S. Pat. No. 5,068,983 (“Marc”) appears to relate to a shoe having a recess extending through the base piece and a heel piece made of cushioning material being placed within the recess. A top cushioning layer is placed over both the base and heel pieces.
U.S. Pat. No. 3,859,740 (“Kemp”) appears to relate to a shoe having a recess extending through multiple layers and a cushion placed within the recess. It appears Kemp requires a part of the recess to be free from any object in order to provide clearance for bone spurs.
However, Erickson and Marc both seem to limit the cushioning to a depth of the insole or base piece, which often represents a fraction of the overall depth of the interior of the shoe. Kemp also seems to have a limited amount of cushioning due to the requirement of a part of the recess to free from being occupied by any object.
What is desired, therefore, is a shoe having improved comfort while reducing moisture content and/or improving breathability. Another desire is to enhance cushioning beyond the limited capabilities of the prior art.